"I don't know if they really thought it was going to be a big thing," Papworth told Sky News.

Texting didn't take off right away. Texting became available in 1993. But in 2011, 73 percent of cellphone owners said they use text messages occasionally. At that time, text message users said they sent or received 41.5 messages per day, according to the Pew Research Center.

More recently, text messages have declined, according to Digital Trends. Apps like Facebook Messengers, WhatsApp and iMessage have limited the range of the regular SMS.

"But texting remains popular due to how easy it is to use," according to Digital Trends. "You don't need Wi-Fi or a data connection to send a text. You just need cell service and a few characters."

Elizabeth Bruton, curator of technology and engineering at the Science Museum in London, called texting an "important development in the history of mobile telephones."

"For the very first time we have mobile telephones that were more than just literal mobile telephones, moving beyond voice communications to a new application of the mobile spectrum — to sending, literally, text messages," she told Sky News. "And we can see that continuation through to today when we have hundreds of thousands of applications on our smartphone. So SMS can be considered the first step towards the modern smartphone."